The duo met with about 20 students, a spokeswoman for Obama said, at the high school located at 6220 S. Stony Island Ave. — across from the future site of the Obama Presidential Center.

"The warm and wide-ranging conversation, lasting over an hour, covered how the Obama Presidential Center will showcase the South Side of Chicago for a global audience, the importance of young people staying inspired and hopeful, and the transformative power of students using their voices to change the world," Obama’s spokeswoman said in a statement.

"Thanks to my friend Prince Harry for joining me today to surprise these remarkable students at Hyde Park Academy on the South Side. We were blown away by their passion, ambition and talent!" she wrote.